One example of a cause of injury and death in acute health care settings is entrapment in bed side rails, such as those of hospital beds. While several designs have been proposed to reduce patient entrapment, the need to have a foldable and adjustable rail at the side of a bed remains in conflict with the need to reduce the risk of entanglement of patient limbs and medical equipment (e.g., pacing wires, ventilator hoses and catheter tubes).
Alarm and monitoring systems may be used in some cases to alert caregivers to movement of at-risk patients, and/or patients may be physically restrained (e.g., especially when there is a ratio of less than one caregiver per patient and it is not physically possible for the patient to be attended to and observed at all times).
U.S. Pat. No. 7,821,415 discloses a “pneumatic patient bed monitor” that uses a pressure monitoring interface underneath the patient to sense the removal of patient weight. Other systems are also designed to sense patient contact or weight using pneumatic or electrical sensors. For example, U.S. Pat. No. 4,633,237 includes “a plurality of sensors defining interstices of a matrix of such sensors.”
U.S. patent application Ser. No. 12/996,034 (published as Pub. No. US 2011/0087079) discloses acoustical patient monitoring using a sound classifier and microphone.